Outdoor Dogbox

Outdoor Dogbox

Technical details

The type GDX outdoor “Dog Box” circuit breaker is available in the following ratings:

  • 11 kV 2500 A 25 kA 95 kV BIL
  • 22 kV 1600 A 25 kA 150 kV BIL
  • 36 kV 1600 A 25 kA 200 kV BIL
  • Mild steel or 3CR12 option
  • Protection relays, metering instruments; current and voltage transformers can be housed in the cubicle.
  • Circuit breakers and cubicles type tested to IEC 60056 at KEMA and by the SABS
  • Developed and manufactured in the Republic of South Africa
  • Used extensively by Eskom


The Alstom ORTHOFLUOR SF6 FP circuit breaker is the ideal circuit breaker for outdoor dog box applications. ORTHOFLUOR circuit breakers are of the separate pole type. The pole units are supported on a common rigid frame which also supports the operating mechanism.
The separate pole unit structure enables the use of different frames and for different pole spacing. Each pole unit consists of an interrupting element housed in an epoxy resin enclosure. The complete range is produced by combining different frames, enclosures and interrupting elements. The interrupting element determines the performance in respect of:

  • Interruption over a given voltage range overcurrent withstand rated current carrying capacity
  • The dielectric performance between input and output and between conductor and earth are determined by the enclosure. The dielectric properties between phases depend only on the pole spacing.

Click here to download the Outdoor Dogbox Brochure.